Variability of the HCS at 15 R_⊙ for the June 14 simulation. In the top panel, the number density, N, and the latitudinal magnetic field, B_θ, are extracted along the HCS and stacked over time. Several propagating flux ropes are going through the domain, with various longitudinal extents, but a rather steady time pattern. In the bottom panel, we show a Fourier analysis over time (for each longitude). For all quantities, the peak is located around a period of 20 h.